Flux Computing designs and manufactures optical processors to train and run inference on large AI models. Join us to be part of a highly motivated and skilled team that thrives on delivering impact and innovation at speed.

The Role

We’re searching for a Senior/Staff/Analog Design Engineer with a strong focus on CMOS analogue design to lead the design, validation and productisation of ultra‑high‑speed (> 10 GHz) transimpedance amplifiers that sit at the electrical-optical front end of our OTPU. The role demands deep expertise in low‑noise, wide‑bandwidth analog circuit design, simulation and measurement. The ideal candidate will pair a solid grounding in semiconductor physics with a passion for building reliable, production‑worthy TIAs that unlock new levels of AI‑hardware performance.

Responsibilities

• Design and develop high‑speed CMOS TIAs – from schematic through post‑layout verification, lab bring‑up and production test – meeting stringent bandwidth, input‑referred‑noise and linearity targets for our optical links.

• Work hand‑in‑hand with opto‑electronic and packaging teams to co‑design the photodiode, package, and PCB interconnect that surround the TIA, ensuring seamless system integration.

• Analyse circuit performance, identify bottlenecks (e.g. excess input capacitance, stability, power), and implement innovative solutions such as inductive peaking, active feedback, or process‑corner tuning to optimise speed, noise and power.

• Mentor junior engineers, run in‑depth design and layout reviews, and champion best‑practice methodologies for high‑frequency, low‑noise analog design.

• Track and bring into the team the latest advances in TIA architectures, CMOS processes, RF‑EDA flows and test techniques to keep Flux at the cutting edge.

Skills & Experience

• 7 + years of industry experience in CMOS integrated‑circuit design with a primary focus on high‑speed, low‑noise analog front ends (TIA, LNA, or similar).

• Mastery of analog/RF EDA flows: schematic capture, SPICE and S‑parameter simulation, layout and parasitic extraction, and post‑silicon characterisation.

• Proven track record of meeting sub‑pA/√Hz input‑referred noise, multi‑10‑GHz bandwidth and tight power budgets in a shipping product.

• Bachelor’s degree in Electrical Engineering (or related); Master’s / PhD a plus.

• Strong problem‑solving skills, especially in feedback stability, transmission‑line effects, package modelling and de‑embedding.

• Excellent collaboration and communication abilities for effective cross‑disciplinary teamwork.

• Demonstrated success in fast‑paced environments where innovation and rapid iteration are paramount.

• A portfolio of personal or open‑source projects – or published papers/patents – that highlights creative analog or RF design thinking.

Frequent travel is expected between our Austin and London offices.

We’re building fast and that includes our benefits. More exciting additions are coming soon for the Flux crew.

If you are passionate about pushing the boundaries of what's possible in AI and thrive in a high-energy, fast-paced environment, we want to hear from you. Apply now to join Flux and be a key player in shaping the future of computing.